The relative orientation of two or more connected objects often can be a critical aspect of the way the objects perform their function. This may be illustrated simply with reference to a golf club, although those skilled in the art will recognise numerous other products and situations where similar issues arise and reference throughout this specification to golf clubs only should not be considered limiting.
A golf club has a shaft connected to a club head through an aperture, called a hosel, in the club head. The relative orientation of the club head with respect to the shaft is a critical element in the performance of the club. Two aspects are particularly important: the lie angle, which relates to an angle between the shaft and a lateral direction through the club head; and the loft angle, which relates to the slope of the club head with respect to a plane through the shaft and the club head. In essence, in the normal golfing stance with a golf club near the contact point with a golf ball, the lie corresponds to the angle between the shaft and the club head, while the loft corresponds to the degree of backward rotation of the club head with respect to the shaft. These two angles relate to rotations of the club head with respect to the shaft about two different axes.
Golf clubs for different shots generally will have different lie and loft angles. However, even for similar clubs (e.g., 8 irons) there is generally a range of lie and loft angles to suit different golfers.
Individual golfers may vary significantly in size, and have vastly differing athletic abilities, and therefore need a variety of custom configurations available to customise their golf equipment. Ideally a golfer should be easily able to change the following:
1. the club length
2. the grip type
3. the shaft type
4. the lie angle
5. the loft
6. the head weight and balance characteristics
In general when a different golf club is required due to a change in the size or stance of the golfer, or a change in their ability, it is necessary to purchase a new club or to alter the existing one.
However the prior art methods for modifying a club are very limited. Specifically the methods used currently are:                1. The club length is only changed by removing the grip, cutting or extending the shaft, and gluing a new grip on.        2. The grip type is only changed by removing the grip, and gluing a new grip on.        3. The shaft type is changed with great difficulty by heating up the hosel area of the club with a gas torch to break the epoxy glue joint, and then gluing a new shaft in place, and waiting for the new glue to cure before playing with the club.        4. The lie angle is changed in a somewhat arbitrary way by applying a lever bar to the shaft (or club head) and pulling hard on the bar. This method can damage the club and is inaccurate.        5. The loft is changed in a similar manner to the lie angle as described immediately above. This method can also damage the club and is imprecise.        6. The head weight and balance characteristics are the only adjustments which have been improved upon in recent years, with some premium branded clubs having weight ports which, allow a set of weights inside the club head to be exchanged.        
In particular there is no current method whereby the relative orientation of the shaft and club head can be adjusted for both lie angle and loft in a precise and controlled manner, nor any method of adjustment that does not have the potential (at least) to cause damage to the club. In practice, when a golfer wishes to change the lie angle or loft of a club it is generally necessary to purchase a new club, which adds extra cost to the golfer.
One consequence of this is the necessity for suppliers of golf clubs to maintain an inventory of clubs that cover the wide variation of lie and loft for each club. If a reliable and accurate method was available for varying the lie and loft of a club then it would be possible for a supplier to stock a smaller range of clubs which could be individually adjusted to the desired settings, thus saving costs to the supplier.
Another issue that could be addressed is the variation that can occur during manufacture of a golf club. It could be that a club may have a lie angle and/or loft that is different than that designated for the club as a consequence of manufacturing variation. It would be useful to have a method of correcting for this which could benefit the golfer by providing an accurately formed club, and the manufacturer/supplier in reduction of discarded clubs due to manufacturing error.
Adjustment of a golf club has been discussed here as an example of a common situation where adjustment of the relative orientation of two objects, in this case a shaft and a club head of a golf club. However the general situation is very common, especially where the orientation of an object with respect to a shaft is involved.
One common situation arises when an object is made to revolve about a shaft, such as a wheel or fan about its axle. In most instances a bearing is used to separate the revolving object from the axle. However, the revolving object can be unbalanced often causing unwanted forces to be applied to the bearing. This generally causes wear on the bearing and can result in the bearing requiring replacement sooner than would be the case for a balanced load.
One common cause of imbalance is a misalignment of the natural axis of rotation of the revolving object with the axis of the bearing. It would be useful to have a bearing that could be adjusted in order to align the axes.
It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.
All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.
It is acknowledged that the term ‘comprise’ may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term ‘comprise’ shall have an inclusive meaning—i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term ‘comprised’ or ‘comprising’ is used in relation to one or more steps in a method or process.
Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.